simplify code per review

Author: SamSaffron

db/post_migrate/20240609232736_drop_commands_from_ai_personas.rb

@@ -5,7 +5,6 @@ def down
   end
 
   def up
-    Migration::ColumnDropper.drop_readonly(:ai_personas, :commands)
-    remove_column :ai_personas, :commands
+    Migration::ColumnDropper.execute_drop(:ai_personas, :commands)
   end
 end